/*
 * Package il.ac.biu.cs.grossmm.impl.activeData
 * File DataRetriever.java
 * 
 * This is a part of presence service framework prototype. 
 * See javadoc for more information.
 *  
 * Copyright (C) 2006 Grossmann Mark
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.

 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

package il.ac.biu.cs.grossmm.impl.activeData;

import il.ac.biu.cs.grossmm.api.OperationFailedException;

/**
 * A data source used by the <tt>Cache</tt> class to obtain
 * data from.
 */
public interface DataRetriever<K, V> {
	/**
	 * Given a key returns a value of this key
	 * @param key a key
	 * @return the value for this key
	 * @throws OperationFailedException
	 */
	V retrieve(K key) throws OperationFailedException;
}
